all of the above!
i too was very messy as a kid & for most of my adulthoood so far. Started to sort myself out a couple of years ago & so glad i did, we ahve a 3.4yr old & 6mnth old & would live under a pile of crap If i hadnt pulled my finger out.
a few tips that worked for us (sorry for any duplicate ideas)........
A little bit each day (after your initial blitz!)
We have a MASSIVE weekly wall planner, magnetic blackboard paint, painted directly on to the wall. we have seperate catergories, housekeeping, admin, kids activity/outing, events & appointments. each catergory has a different coloured strip of paper stuck to tiny magnets. Jobs get written on the strip & stuck on wall calender as & when they come along, if it doesnt get done that day it gets moved on to the next day. All house keeping jobs, change beds, clean loo`s that get done regularly/every week, get divvyied out aroung the other more fun activities. (we hardly look at planner for day to day jobs now, become second nature!) you can also write drectly on the blackboard with chalk. The weekly grid is done in chalk pens. This is a bit of a pain to begin with but have found it massivly helpfull. my husband is dyslexic and its has really helpped him put some visual order in his week. My little boy loves it now as well & enjoys picking activities out of the tub & putting them on himself ;)
I have lots of medium sized stacking boxes with lids, all labled, cars, people, animals, shop & food etc - found it much easy to tidy stuff away (especially with 3yr old helping) and then find it again when you need it. we have a couple of mixed boxes, labeled thus for weird odds and sods you end up with.
Lots of samller tubs/boxes for craft stuff, for same reason.
Purge regulary - take stuff to charity shop, local hostal etc. It good for kids to know some others have less than them. If it becomes habit for you it will ve hait for your little one too.
ask people not to get large pressies - darling would llove some books this christmas/birthday usually works ;)
Never leave a room/go up or down the stairs with out taking something with you & putting it away.
Im sure there are more, but for now, finally, let some things go, not everything has to be squeeky clean & mum tidy ( my mum has loads of storage too ;( ) for example, my windows havnt beeen cleaned since we moved in, just not a priority. ill wash them when we move out.
good luck op, you can do it!